1H MR spatially resolved spectroscopy of human tissues in situ.

SPAtially Resolved Spectroscopy (SPARS) has been developed as a method to obtain localized MR spectra in a whole body MRI system. It is based upon a combination of selective and non-selective pulses such that longitudinal magnetization is preserved in a particular volume of interest (VOI), whereas outside this volume the magnetization is dephased in the transversal plane. After this selection phase the spectrum of the VOI can be obtained after a single excitation pulse. In this respect it is similar to the VSE sequence as proposed by Aue et al. The difference is that even by using relatively large body and head coils the SPARS sequence requires much lower rf powers levels, such that it can be implemented on a whole body MRI system.